The invention described herein relates to method and apparatus for interconnecting a standard format fiber optic connector plug to a sleeve based connector to facilitate the connection of optical fibers with electro-optic systems.
Due to increasing needs for bandwidth, modern computer and communication networks are placing increasing reliance on optical signal transmission through fiber optic cabling. With fiber optic cabling, data is transmitted using light signals, not electrical signals. For example, a logical xe2x80x9c1xe2x80x9d may be represented by a light pulse of a specific duration and a logical xe2x80x9c0xe2x80x9d may be represented by the absence of a light pulse for the same duration. In addition, it is also possible to transmit at the same time multiple colors of light over a single strand of optic fiber, with each color of light representing a distinct data stream.
While fiber optic cabling is very efficient for transferring data, such light signals can not, as yet, be effectively used to process data. Therefore, many existing networks use fiber optics for transmitting data between nodes and silicon chips for processing the data electronically within the nodes.
Electro-optic circuitry, such as fiber optic transceivers, which convert light signals from a fiber optic cable into electrical signals, and vice versa, are used as the interface between a fiber optic line and a computer node. A typical transceiver includes a substrate and one or more electro-optic (also referred to as opto-electronic) semiconductor devices mounted on the substrate. These electro-optic semiconductor devices can include optical detectors for converting light signals received over the fiber optic cables into electrical signals or optical emitters for converting electrical signals from the semiconductor devices into light signals. Such electro-optic devices are referred to herein as photonic devices. Typical examples include, but are not limited to optical emitters (e.g. laser devices) and optical receivers. These photonic devices can be incorporating into a varying array of optical transmitters, receivers, and transceivers. Such devices are widely available. For example, a number of fiber optic transceivers are commercially available from Hewlett Packard, AMP, Sumitomo, Nortel, and Siemens.
In order to efficiently route and interface optical signals with the photonic devices of the nodes, optical fibers are in optical communication with opto-electronic devices at the nodes. Commonly, the opto-electronic devices are arranged on a connector apparatus to facilitate the easy interconnection of the opto-electronic devices with the optical fibers. In common usage, the opto-electronic devices include photonic devices arranged relative to a connector apparatus in a specified configuration which is in accord with one of a number of standard configurations. Such configurations are referred to herein as formats. By configuring the photonic devices of an opto-electronic device and connector in accord with one of the common formats, any optical fiber arrangement configured in accordance with the same format can be interconnected to a corresponding opto-electronic device. Such optical fibers are appropriately arranged in a specific format and bundled together in a connector plug having the desired format.
A brief description of some standard formats follows. Generally, optical fibers are bundled together and held in a ferrule. A ferrule is mechanical fixture used to protect and align the fibers in a connector. Commonly, such ferrules are made of ceramic materials. One common format is a so-called MTP-format. An MTP connector is a small form factor connector that permits high density fiber solutions using US Conec MT ferrules. This format is also referred to as MPO (multiple parallel optics) format. Generally, twelve or more fibers per connector are bundled together in a small diameter cable. Another commonly used format is the MT-RJ format. The MT-RJ format is a small form factor, dual fiber connector. Another commonly used format is the MT-BP format. The MT-RJ format is a small form factor, high fiber count fiber connector (sometimes having as many as eighty fibers). In addition to the few formats described above, there is a relatively wide range of other standard ferrule-based parallel multi-mode fiber formats in common usage. Such formats are known to those having ordinary skill in the art. One of the difficulties of such formats is that they are relatively large, thereby limiting the number of fibers connectable using such formats.
National Semiconductor has developed a family of sleeve based connectors for interconnecting optical fibers to electro-optic devices. One such sleeve based connector is a miniature form factor connector which creates smaller, higher density connectors for connecting optical fibers to electro-optic devices. However, the small size and miniaturized format of such connectors make them incompatible with existing standard format connectors. As a result their exists a need for making the miniature form factor connectors backward compatible with existing legacy formats (such as MPO, MTP, MT-RJ, MT-BP, and other standard formats).
Embodiments of the invention include an adaptor apparatus for optically connecting optical fibers of a standard ferrule based parallel multi-mode fiber format plug with photonic devices of a connector sleeve arranged in accordance with a miniature form factor format. The adaptor includes an adaptor jacket having a first end and a second end, the first end being in optical communication with the second end. The first end is configured to receive a connector plug having optical fibers arranged in a standard ferrule based parallel multi-mode fiber format. The second end is formatted for connection with a miniature form factor connector sleeve having an optical subassembly fitted thereon. Thus, the photonic devices of an optical subassembly arranged in the miniature form factor format can be optically coupled, via the adaptor jacket, to corresponding optical fibers of the connector plug arranged in a standard ferrule based parallel multi-mode fiber format.
In another embodiment, the invention includes an adaptor apparatus for facilitating the optical interconnection of optical fibers arranged in a standard format connector plug with photonic devices arranged in miniature form factor format on an optical subassembly of a miniature form factor connector sleeve. The adaptor apparatus comprises an adaptor jacket having a first end and a second end. The first end of the adaptor jacket is configured to receive a standard format connector plug and the second end is configured for connection with a miniature form factor connector sleeve. The first end is optically connected to the second end using an optical ribbon containing optical fibers. The optical fibers being arranged at the second end of the adaptor jacket in accordance with a miniature form factor format to optically interface with photonic devices arranged in the same miniature form factor format and arranged at the first end of the adaptor jacket in accordance with a standard format to optically interface with optical fibers arranged in the same standard format in a connector plug, whereby the plurality of optical fibers of the optical ribbon transmit light between the photonic devices and corresponding optical fibers of the plug.
The invention further includes a method embodiment for interconnecting optical fibers carried by a connector plug arranged in a standard format with photonic devices arranged in a miniature form factor format. The method comprising providing a plug having a plurality of optical fibers arranged in accordance with a standard format and providing a connector having a plurality of photonic devices arranged in accordance with a miniature form factor format. The method further includes providing an adaptor having a first optical interface configured to optically connect with the plug having plurality of optical fibers arranged in accordance with the standard format and having a second optical interface configured to optically connect with the with the plurality of photonic devices arranged in accordance with the miniature form factor format. The method further comprising connecting the plug to the first optical interface of the adaptor and connecting the second optical interface of the adaptor to the plurality of photonic devices of the connector.